Table 2.

Grading score for qualitative image analysis

Grading score	Qualitative analysis
	Subjective noise	Sharpness	Artefacts	Diagnostic acceptability
1	Unacceptably noisy	Blurry	Affecting diagnostic information	Unacceptable
2	Better than one, poorer than three	Poorer than three	Major artefacts affecting the visualization of normal structure	Better than one, poorer than three
3	Some noise in an acceptable image	Minor burring in an acceptable image	Minor artefacts not affecting the visualization of any structure	Probably confident
4	Better than three, poorer than five	Better than three, poorer than five	Absent	Better than three, poorer than five
5	Minimal or no noise	Sharpest	Not applicable	Best